Many times over the course of the first day of the second annual ASADI conference, participants somberly outlined and reiterated the numerous obstacles facing the endeavor to incorporate evidence-based guidance from the scientific community into public policies. Indeed, as the presentations made clear, many challenges confront both policymakers and scientists: limited contact between government leaders and scientists, frequent turnover of politicians; the often esoteric nature of science, and different terminology that can frustrate mutual understanding are just a few of the barriers.

But as several presentations showed, scientists in Africa are having a positive influence on their government decision-makers and ultimately on the public at large.

Urbain Olanguena Awono, Cameroon minister of public health, highlighted some key ways that science-based guidance has resulted in tangible results. Noting that 40 percent of the nation's children ages 5 and under suffer from vitamin A deficiency, he pointed to an initiative to integrate vitamin A supplementation in the Expanded Program on Immunization. And he pointed to a nutrition outreach program for HIV/AIDS patients in the community, and also credited efforts to increase rates of breast-feeding for bringing up the proportion of women who solely breast-feed their infants to nearly 30 percent from less than 1 percent in the early 1990s. He also praised the adoption of iodizing salt for reducing the rate of goiters from more than 29 percent in 1991 to about 5 percent in 2002.

Salt iodization as a case study for the impact that scientifically generated, evidence-based guidance can have was described in detail in a talk by Daniel Lantum, Cameroon's former minister of public health and regional coordinator for Africa's International Council for Control of Iodine Deficiency Disorders. In the early 1990s, Lantum headed an initiative to survey rates of goiter across the country, ultimately determining that more than a quarter of the population suffered from this condition. He and colleagues took the information to the ministry of public health and convinced them that action was urgently needed. The only problem was the best solution based on the evidence -- iodization of salt -- required industry involvement. After all, the salt producers had to be motivated to change their processes. This case, Lantum noted, illustrates the necessity as well as the ability to bring together not only scientists and policymakers, but also government officials from different ministries to solve a problem. Ultimately, through collaboration, iodized salt production increased from zero to 90 percent within the first nine years after policymakers mandated iodizing, and the rate of goiters among the population has dropped to around 5 percent today -- as verified by additional scientific surveys.

This initiative worked in part because there were people with scientific backgrounds in the government as well as concerned scientists and champions of the cause in the community. Also, the scientists developed a comprehensive database of evidence and pursued partnerships and links with industry to enact changes.

The Nigerian Academy of Sciences entered the sometimes difficult nexus of politics and science a few years ago when its members responded to the spate of new clinics claiming to offer cures for HIV/AIDS after the pandemic flared up in Nigeria. Government officials as well as the public were lured into trusting these clinics; even the military sent personnel to be treated in such places, noted David Okali, president of the Nigerian Academy of Sciences. To advise their government leaders, the academy convened a panel that examined the claims made by the individuals running these clinics, and concluded that scientific evidence to support them was lacking. Since the panel's report was published, the government has moved away from patronizing these clinics, he noted.

Currently, much of science's influence on policymaking in Africa results from proactive efforts by scientists to reach out to their governments and grab their attention. The Academy of Science of South Africa has recently embarked on a study to review scientific evidence about nutritional influences on human immunity, with a particular interest on the possible interactions between malnutrition and HIV/AIDS and tuberculosis. ASSAf members initiated the project themselves with the goal of determining whether evidence supports making changes to the recommended daily allowances of nutrients in South Africa; whether special advice should be given to HIV-positive individuals; and to recommend priorities for further research to address remaining knowledge gaps. It is also the academy's first attempt to conduct a study by an impartial panel of scientists that would review and weigh the existing evidence and issue objective, scientifically guided policy recommendations. What its impact on South African leaders will be remains to be seen, said Barry Mendelow, chair of the study. But given other examples of how scientific evidence, presented in an understandable, influential manner has yielded fruitful policy decisions, ASSAf's project and other academy's endeavors are worth pursuing.